IC16 Hypertension in Pregnancy + Contraception Flashcards
What are the BP cuts off for hypertension in pregnancy and when to start treatment?
BP cut offs:
- HTN: >140/90 mmHg (2 measurements, at least 4 hr apart) –> START TREATING*
- Severe HTN: >160/110mm Hg (2 measurements)
What are the 4 different types of hypertension in pregnancy?
Chronic HTN
* Pre-existing HTN / new onset HTN before 20wks gestation
Gestational HTN
* New onset HTN after 20wks gestation
* No proteinuria
Pre-eclampsia
* New onset HTN after 20wks gestation
* New onset of Proteinuria / end organ dysfunction / uteroplacental dysfunction after 20wks
Chronic HTN with superimposed pre-eclampsia
* New onset proteinuria before 20wks gestation
* Chronic HTN (pre-existing)
What are some test / labs to look at to see whether the patient has pre-eclampsia?
What are the severe symptoms of eclampsia?
Pre-eclampsia:
- Test for Proteinuria:
a. 24hr urinary protein > 300mg
b. Dipstick protein >= 2+
c. Urine protein:creatinine ratio > 0.3 mg/dL - Test for end organ damage
a. Low platelet count –> liver damage
b. LFT > 2x ULN
c. Doubling of SCr in the absence of other renal disease
d. Pulmonary edema
e. Neurologic complications – onset of headaches, visual disturbances, seizures
Rapidly progress to eclampsia
* tonic-clonic, focal, multifocal seizures superimposed on preeclampsia
* medical emergency
how to prevent pre-eclampsia? In which patient groups?
Prevention of Pre-eclampsia:
Low dose aspirin 100mg or 150mg daily
- give to high-risk patients e.g.
o HTN in previous pregnancy
o multifetal gestation (twins/triplets)
o autoimmune disease
o DM
o CKD
o lupus nephritis - start after 12 weeks of gestation (after 1st trimester) and before 16 weeks, continue till delivery
- hypothesize MOA: helps to increase uteroplacental blood flow by inhibiting thromboxane A2
What are the possible treatment options for hypertension in pregnancy?
Medication
- Methyldopa
* Huge amt of evidence on safety
* Rarely used due to low potency + increase ADR (sedation, dizziness) - Labetalol
* Commonly used
* Lower adverse effects on uteroplacental blood flow and fetal growth than beta blockers
* ADR: bronchoconstriction (avoid in asthma/COPD), bradycardia
* Alpha + beta blocker - Nifedipine ER
* Commonly used
* ADR: pedal edema, flushing, headache - Hydrochlorothiazide
* 2nd /3rd line
* Interferes with normal blood volume expansion in pregnancy (since it is a diuretic which reduces blood volume) - Hydralazine
* Rarely used
* ADR mimics symptoms of severe pre-eclampsia + imminent eclampsia: N&V, palpitation, flushing, headache, tremor
Avoid ACEi / ARBs in pregnancy
What are the 2 main MOA of contraception?
2 Main MOA:
- Prevent fertilization – Prevent sperm from coming into contact with mature ovum / Prevent ovulation
- Prevent implantation of fertilized eggs on to the endometrium
What are the barrier methods, their CI, Pros and cons? What is the failure rate?
Barrier Techniques Contraindications Pros Cons
- External Condom (male)
Contraindication:
Allergy to material (latex/rubber)
Pros:
STD protection
Cons:
High failure rate
Poor acceptance
Possibility of Breakage
- Internal Condom (female)
CI:
Allergy to material (polyurethane)
History of toxic shock syndrome (TSS)
Pros:
STD protection
Inserted ahead of time
Cons:
High failure rate
Uncomfortable with ring hanging outside
- Diaphragm with spermicides and Cervical Cap
CI:
Allergy to material (latex/rubber/spermicide)
Recurrent UTIs
History of TSS
Abnormal gynecological anatomy
Pros:
Reusable
Low cost
Cons:
High failure rate
Low STD protection
Increase risk of UTI
Cervical irritation
- Failure rate / rate of pregnancy 13-21%
What are examples of estrogen?
What are the MOA of estrogen?
What is the high dose estrogen?
When to use high dose?
Estrogen
- MOA:
suppress FSH release, prevent ovulation
mainly stabilize endometrial lining & provide cycle control - Examples: Ethinyl estradiol, Estradiol valerate, Esterol, Mestranol
- Low dose: 20-25 mcg (default)
- High dose: 30-35mcg
Obesity / weight > 70.5kg
Early / mid cycle breakthrough bleeding or spotting (mimic normal cycle)
Non-adherent
What are examples of progestrerone?
What are the MOA of progestrerone?
When to use high dose?
Progestin
- MOA:
thickens cervical mucous prevent sperm penetration, slowing tubal motility (delay sperm transport), induce endometrial atrophy
blocks LH surge, prevent ovulation
provides most of the contraceptive effects - Variable activity and androgenic effects
- Examples:
(1st gen) norethindrone, ethynodiol diacetate, norgestrel, norethindrone acetate
(2nd gen) levonorgestrel
(3rd gen) norgestimate, desogestrel
(4th gen) Drospirenone - MOA: mild diuretic similar to spironolactone, anti-androgenic, cause less water retention, less acne
- ADR: hyperkalemia, thromboembolism, bone loss
(4th gen) Cyproterone - MOA: anti-androgenic, antigonadotrophic, primary indication: severe acne, hirsutism
- should not be use alone for contraception
- ADR: thromboembolism
o Higher dose:
Late cycle breakthrough bleeding
Painful menstrual cramps
How to categorize COC? What are the pros and cons of each type of COC?
Relative Amount
Monophasic
Definition:
Same amount of estrogen and progesterone in every pill
Pros:
- Less confusing
- Convenient (simpler missed dose)
Multiphasic:
Variable amount of estrogen and progesterone for different pills
(usually, more E in front and more P at the end of cycle)
Pros:
- Less progestins –> less ADR
Duration:
Conventional / New formulation
Definition Conventional:
21 days (pills) + 7 days (placebo)
New formulation:
24 days (pill) + 4 days (placebo)
Pros & Cons Conventional: Mimic normal cycle
New formulation: Reduce hormonal fluctuations –> less ADR
Extended / Continuous
Extended:
84 days (pills) + 7 days (placebo)
Continuous:
no placebo
Pros:
- Convenient (Lesser periods)
Cons:
- may have breakthrough bleeding
What are the different initiation methods for COC?
- First Day:
Start on 1st day of menstrual cycle
No need back up contraceptive required
(Since they have 5-6 pills once period ends)
Simplest method
Mimic normal Cycle - Sunday Start:
Start on the 1st Sunday after menstrual cycle begins
Need back up contraceptive for at least 7 days
(Need to rely on other methods such as barrier technique / abstinence)
Ensures that menstrual does not occur on weekends
(the 22nd day after 21 days of pills will be a Sunday, and ideally the next day or Tuesday will be the start of the next cycle)
- Quick Start:
Start now
Need back up contraceptive for at least 7 days & potentially until the next menstrual cycle begins
(Need to rely on other methods such as barrier technique / abstinence)
Convenient if need to start asap
What are some considerations when choosing COC?
Considerations in choosing COC:
- Hormonal content required
* Higher dose estrogen for obese or weight > 70.5kg, non-adherent, early or mid-cycle breakthrough bleeding - Convenience
* (adherence/administration) Monophasic –> since less complicating, no need to worry which pill to take for different days + missed dose instructions are simpler
* (Want less menses) extended or continuous COC –> 1 period in 3 months or no period at all - Tendency for oily skin, acne, hirsutism (androgenic issues)
* Avoid giving progestins with androgenic effects
* Give alternatives e.g. drospirenone, cyproterone - Medical conditions
* Dysmenorrhea, cramping give more progestins / extended / continuous COC / new formulations
* PMS, PCOS etc.
What are the benefits of using COC?
Benefits:
- Prevent pregnancy
- Improve menstrual irregularity (conventional / new formulation)
- Relief menstrual related issues e.g. cause amenorrhea (specifically continuous regime), dysmenorrhea, menorrhagia
- Antiandrogenic effects (specifically progestins drospirenone, cyproterone)
- Improve perimenopause
- Efficacious against polycystic ovarian syndrome (PCOS), premenstrual syndrome (PMS), premenstrual dysphoria disorder (PMDD)
- Iron-deficient anaemia (progestins since it can lead to amenorrhea)
- Reduce risk of ovarian and endometrial cancers
- Reduce risk of ovarian cysts, ectopic pregnancy (fertilized egg implants outside of uterus), pelvic inflammatory diseases, endometriosis, uterine fibroids, benign breast disease
What are the possible CI for COC?
Contraindications:
- Breast Cancer
- Venous thromboembolism / DVT / PE
- Ischaemic stroke / Myocardial infarction
- Immobilization after major surgery
- <21 days of postpartum
- Thrombogenic mutations
- Migraine with auras
- BP > 160/100 mmHg
- HTN with vascular disease
- Ischemic heart disease
- Cardiomyopathy
- Smoking >= 15 sticks/day AND >= 35 y/o
- History of cerebrovascular disease
Which component of COC increases a person’s risk to breast cancer?
When to avoid COC due to risk of breast cancer?
Breast Cancer
- Caused by COC (both estrogen and progesterone components)
- Risk factor: long duration use, >40 y/o
- Avoid in
women > 40y/o,
family history of breast cancer,
PMH or current breast cancer (within 5 years) - Risk reduces to normal when discontinue